A new RedisDatabase instance that can be used to access the database.
// connecting with default settings: auto redisDB = connectRedisDB("redis://127.0.0.1");
// connecting using the URL form with custom settings auto redisDB = connectRedisDB("redis://password:myremotehost/3?maxmemory=10000000");
Returns a Redis database connection instance corresponding to the given URL.
The URL must be of the format "redis://server[:port]/dbnum".
Authentication: Authenticated connections are supported by using a URL connection string such as "redis://password@host".